1. Field of Disclosure
The present disclosure relates to a hydrolyzing method and apparatus, and more particularly to a method for hydrolyzing an organic solid and an associated preprocessor for anaerobic digestion treatment.
2. Related Art
Generally, most of the present organic solid processing is performed in the manner of digesting organic solids by aerobic or anaerobic microbes, to achieve the effect of reducing the quantity of the solids. However, such biological digestion process costs considerably long time. In order to shorten the time needed by the biological digestion process, a chemical or physical pretreatment is mostly adopted. The pretreatment is used to decompose or crack the organic solids from large molecules to small molecules, so as to increase the digestion speed of the aerobic or anaerobic microbes, and effectively shorten the overall digestion time of the organic solids.
A well-known and common chemical pretreatment method is a method of alkaline hydrolysis, which includes the following steps. An organic solid is guided into a processing tank, precipitated and hydrolyzed by adding alkali, and then dried for recovery. However, the overall processing time of the organic solid is increased. The added chemical will not only increase salts in the original organic solid, but also may cause secondary damage on environment, such as chemical pollution. Therefore, the chemical pretreatment should be performed very cautiously, and thus the application of the chemical pretreatment is always limited. Moreover, organic fertilization cannot be achieved after performing the chemical pretreatment, and thus the value of the organic solid after treatment is reduced.
Further, well-known and common physical pretreatment methods generally crack by means of giving external forces, and the most common method includes the following steps. An organic solid is mixed with water, and then hydrolyzed by applying an ultrasonic wave, to crack the organics in the organic solids by means of the energy of the ultrasonic wave in the water, so as to facilitate the digestion of the aerobic or anaerobic microbes, thus reducing the overall digestion time of the organic solids.
Briefly, the physical pretreatment by cracking with an ultrasonic wave may prevent the secondary environment pollution that may be caused by chemical pretreatment, but the generation of the ultrasonic wave needs to be driven by an external power supply, especially for treatment of a large quantity of organic solids, which will definitely consume a large amount of power. Therefore, it is always an objective for related manufacturers to strive to find a method or means capable of reducing the operation time of ultrasonic wave while maintaining the same cracking efficiency of the ultrasonic wave or capable of achieving a higher efficiency of organic solid hydrolysis with the same operation time of ultrasonic wave.